Related Experiment Video
Updated: May 28, 2026

High-throughput Screening for Protein-based Inheritance in S. cerevisiae
Published on: August 8, 2017
Mutability of prions
Jiali Li1, Sukhvir P Mahal, Cheryl A Demczyk
1Department of Infectology, Scripps Florida, 130 Scripps Way, Jupiter, Florida 33458, USA.
Abstract:
Murine prions transferred from brain to cultured cells gradually adapt to the new environment. Brain-derived 22L prions can infect neuroblastoma-derived PK1 cells in the presence of swainsonine (swa); that is, they are 'swa resistant'. PK1 cell-adapted 22L prions are swa sensitive; however, propagation in swa results in selection of swa-resistant substrains. Cloned, PK1 cell-adapted 22L prions were initially unable to develop swa resistance ('swa incompetent'); however, after serial propagation for 30-90 doublings, four of nine clones became swa competent, showing that swa-resistant 'mutants' arose during replication. Mutations in the case of prions are attributed to heritable changes in PrP(Sc) conformation. One clone remained swa incompetent even after 10(35)-fold expansion; surprisingly, after propagation in brain, it yielded swa-resistant prions, indistinguishable from the original 22L population. Thus, cell-adapted 22L prions assumed either mutable or virtually immutable conformations; however, when passaged through the brain all became mutable. Mutability is thus a substrain-specific attribute.
Related Concept Videos
Mutations in Microorganisms
Amyloid Fibrils
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Mutations
Mutations
Chromosomal Alterations Are Large-Scale Mutations
While point mutations are changes in a single nucleotide in...
Mutations
Viral Mutations

